The pounding pain that corresponds with heartbeat. It makes me think there are nerves that register this all the time but there's some part of the nervous system that filters that signal out.

If you have pounding pain from heartbeat, you should go see a doctor. That is not normal.

One feature of migraines is not just a headache. Some people can feel it coming, called the aura. I feel weird during and after the headache. I frequently get the migraine weird feeling without the headache, so-called silent migraine. Migraines and normal headaches feel different.

I would suspect it is increased blood flow.

That's why you get a headache from caffeine withdrawal at least, because the blood flow to your brain increases and you then feel the pounding.

Also tinnitus is said to always be present but the brain can fail to filter it sometimes.

Like right now for me wtf